User Guide

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Chapter 26
Linear Regre
ssion Options
Figure 26-7
Linear Regression Options dialog box
The following options are available:
Stepping Method Criteria. These options apply when either the forward, backward, or
stepwise variable selection method has been specified. Variables can be entered or
removed from the model depending on either the significance (probability) of the
F value or the F value itself.
 Use Probability of F. A variable is entered into the model if the significance level of
its F value is less than the Entry value and is removed if the significance level
is greater than the Removal value. Entry must be less than Removal, and both
values must be positive. To enter more variables into the model, increase the
Entry value. To remove more variables from the model, lower the Removal value.
 Use F Value. A variable is entered into the model if its F value is greater than the
Entry value and is removed if the F value is less than the Removal value. Entry
must be greater than Removal, and both values must be positive. To enter more
variables into the model, lower the Entry value. To remove more variables from
the model, increase the Removal value.
Include constant in equation. By default, the regression model includes a constant
term. Deselecting this option forces regression through the origin, which is rarely
done. Some results of regression through the origin are not comparable to results